Combination latch and interlock system



July 21, 64 M. R. KAUFFMAN 3,141,713

- COMBINATION LATCH AND INTERLOCK SYSTEM Filed May 15, 1965 INVENTOR MELVIN R. KAUFFMA -us ATTORNEY United States Patent 3,141,713 COMBlNATlON LATCH AND INTERLOCK SYSTEM Melvin R. Kauffman, Louisville, Ky., assignor to General Electric Company, a corporation of New York Filed May 13, 1963, Ser. No. 279,767 1 Claim. (Cl. 312-223) This invention relates to a combination latch and interlock system particularly adapted for use in a home appliance.

It is desirable, and in some circumstances imperative, to provide means to insurethat a closure member for a home appliance is secured before the appliance is operated. For example, the operation of an automatic dishwasher involves vigorous liquid spray action within the dishwasher. If the spray action is initiated When the dishwasher closure member is unsecured, liquid will escape from the machine. The same is true with regard to certain types of clothes washing machines. For example, a front loading clothes washing has the access opening below the normal water level so that, if the door is not properly secured, liquid can escape from the machine upon initiation of operation. There are, of course, other applications wherein it is desirable to prevent operation of a device until a closure for the device has been secured.

Accordingly, it is an object of this invention to provide an improved means to insure that a closure member for a device has been secured before operation of the device may be initiated.

It is another object of this invention to provide, in a home appliance, means to prevent operation of the appliance until the appliance door has been closed and latched.

It is a further object of this invention to provide an improved combination door latch and interlock for a home appliance.

Briefly stated, in accordance with one aspect of the invention, there is provided a cabinet having a door. An electrical connector is carried by the cabinet and a guard is biased toward a connection-preventing position wherein it prevents connection between the connector and a source of electrical energy. The guard is adapted to be moved out of connection-preventing position when the door is closed.

In a specific embodiment of the invention, a hasp is secured to the door and is provided with an aperture. The aperture comes into registry with the connector so that when a mating connector is connected to the machine, the mating connector serves as a latching means due to its cooperation with the hasp.

While the specification concludes with a claim particularly pointing out and distinctly claiming the subject matter which is regarded as the invention, it is believed the invention will be better understood from the following description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a side elevational view of a dishwasher employing the present invention; and

FIGURE 2 is a perspective view of the present invention partially cut away to show details of the invention.

Referring now to the drawings, and particularly to FIGURE 1, there is shown a dishwasher having a top opening door 11 pivotal about hinge means 12. The dishwasher 10 contains racks 13 and 14 designed to support dishes or other items to be cleansed by the dishwasher 1t). Also disposed within the dishwasher 10 are a rotating spray arm 15, elevating spray means 16 to efficiently distribute cleaning fluids over the dishes supported by rack 13, an electric heating unit 17, and a motorpump unit 18.

The structure thus far described is not critical to the present invention and, therefore, may be conventional in form. For a more complete disclosure of the structure thus far described, reference may be made to United States Patent No. 3,084,701, issued to A. L. Hardy et al. on April 9, 1963, and assigned to the General Electric Company, the assignee of the present invention.

In accordance with the invention, a combined latch and interlock mechanism shown generally as 19, is provided to insure that door 11 is secured in its closed position before dishwasher 10 may be operated. Reference is now made to FIGURE 2, wherein the combined latch and interlock mechanism 19 is shown in detail. Door 11 is provided with a hasp 20 having an aperture 21 therethrough. The front wall of the dishwasher 10 comprises an inner wall 22 and a spaced outer Wall 23. The outer wall 23 is bent to form surface 24 which extends into engagement with inner wall 22. Inner wall 22 supports an electrical connector 25 having contacts 26 which are electrically connected to the operational elements of the dishwasher 10 through a cycle control means (not shown).

A guard 27 is rotatably secured to the connector 25 by means of shaft 28. Spring means 29 normally bias the guard 27 into registry with the contacts 26 to thereby prevent connection of contacts 26 with an external source of electrical energy.

Surface 24 is provided with a slot 30 which is adapted to receive hasp 20 as door 11 is brought into sealing engagement with a gasket 31. Guard 27 has a laterally projecting surface 32 which is adapted to be engaged by the hasp 20 as the door 11 closes. As closing of the door 11 continues, after engagement between hasp 20 and surface 32, guard 27 is pivoted out of registry with contacts 26. Outer wall 23 is provided with an opening 33 in registry with contacts 26 to allow an external mating connector 34 to be inserted through wall 23 into engagement with contacts 26.

With the arrangement as just described, electrical connection between connectors 25 and 34 is prevented due to the obstruction of guard 27 when the door 11 is not fully closed. However, as door 11 is closed, hasp 20 passes through slot 30 and into engagement with surface 32 whereupon guard 27 is pivoted out of its obstructive position and, as door 11 comes into sealing engagement with gasket 31, aperture 21 in hasp 20 comes into registry with opening 33 and contacts 26 so that the mating connector 34 may be passed through opening 33 and aperture 21 to make electrical connection with contacts 26.

It should therefore be clear that the present invention provides a simple but positive means of insuring that the closure member 11 is properly secured before the dishwasher 10 can be put into operation.

The specific embodiment illustrated in FIGURE 2, in addition to preventing operation of the dishwasher 10 until the door 11 is properly closed, further provides a novel latch means for the door 11. This is achieved by the novel arrangement of opening 33 in outer wall 23, aperture 21 in hasp 2t and contacts 26 of connector 25. The aperture 21 comes into registry with contacts 26 when door 11 is brought into sealing engagement with gasket 31 so that when mating connector 34 is connected to contacts 26, the mating connector 34 serves as a latch since its cooperation with aperture 21 secures door 11 against opening.

As will be evident from the foregoing description, certain aspects of the invention are not limited to the particular details of the construction of the example illustrated, and it is contemplated that various and other modifications or applications will occur to those skilled in the art. It is therefore intended that the appended claim shall cover such modifications and applications as do not depart from the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

An interlock system comprising:

(a) a cabinet having an access opening,

(b) a closure member for said access opening,

(c) a hasp carried by said closure member and having an aperture therein,

(d) a slot in said cabinet adapted to receive said hasp when said closure member is closed,

(e) a first electrical connector member carried by said cabinet and positioned to be in registry with the aperture in said hasp when said closure member is closed,

(1) an opening in one Wall of said cabinet in registry with said electrical connector member,

g) a second electrical connector member adapted to mate with said first electrical connector member to thereby conduct electrical energy to said cabinet, and (h) guard means movably supported by said cabinet and spring-biased into registry with said opening to prevent insertion of said second connector member, (i) said hasp and said guard means being positioned so that said hasp engages and moves said guard means out of registry with said opening when said closure member is closed.

References Cited in the file of this patent UNITED STATES PATENTS 2,585,919 Davis Feb. 19, 1952 FOREIGN PATENTS 468,251 Great Britain July 1, 1937 614,730 Germany Dec. 7, 1933 

